THE Australian military has offered to send almost 300 troops to help rebuild fire-ravaged Blue Mountains communities, in a mea culpa from Defence for starting one of the major blazes.

In what has been described as an "unconventional" move by the ADF, it has also indicated it could build temporary accommodation to billet families who have lost homes and offer psychological support to traumatised survivors.

If the NSW government accepts the offer soldiers would be deployed with helicopters, engineering support and dump trucks, with a focus on rebuilding community facilities destroyed by the fire sparked by bungled explosives training.

Of 270 troops offered to the recovery effort, 50 would work to rebuild community facilities around Lithgow, where the State Mine fire razed three homes and burned 50,000ha of bushland after spreading from a Defence training facility.

A letter from Emergency Management Australia to the state government yesterday revealed Defence would offer its help directly to Lithgow council if its wider offer was rejected by the state government.

Defence wants to work on rebuilding with community groups ineligible for government support, the letter said.

"Should NSW not seek formal recovery support Defence would nonetheless welcome the opportunity to engage with local government, particularly the City of Lithgow, to identify community groups and organisations that might benefit from such support, should NSW be agreeable to this," EMA director-general Mark Crosweller wrote.

Mr Crosweller said 50 troops could work for five days in the region around Lithgow.

Up to 100 soldiers with engineering capabilities could be sent to the Blue Mountains region and other fire affected communities, and up to 120 general labourers and communications and logistics specialists sent from the Army Reserve.

The offer, which included reference to past Defence support in the wake of disasters which has included construction of temporary housing and psychological support teams, included "capabilities ... above those usually made available".

Help from the army would come at no cost to the NSW government and the federal government is expected to make the offer of assistance public today.

It is rare for the ADF to offer support of its own volition and it usually waits for a formal request from the government.

The NSW government is yet to formally respond to the offer. "It is unconventional," a senior federal government source said.

Late last week, Acting Chief of Defence Air Marshall Mark Binskin apologised for the bungled explosives training which sparked the blaze.

This followed the RFS's findings that the blaze was sparked by explosives training on army land at Marangaroo on October 16.

Defence has not offered compensation and is continuing to investigate the circumstances of the fire.

In what has been described as an "unconventional" move by the ADF, it has also indicated it could build temporary accommodation to billet families who have lost homes and offer psychological support to traumatised survivors.

If the NSW Government accepts the offer soldiers would be deploployed with helicopters, engineering support and dump trucks with a focus on rebuilding community facilities destroyed by the fire sparked by bungled explosives training.

Of 270 troops offered to the recovery effort, 50 would work to rebuild community facilities around Lithgow where the State Mine fire razed three homes and burned 50,000 hectares of bushland after spreading from a Defence training facility.

A letter from Emergency Management Australia to the NSW government yesterday revealed Defence would offer its help directly to Lithgow council if its wider offer of help was rejected by the state government.

Defence wanted to work on rebuilding efforts with community groups ineligible for government support, the letter said.

"Should NSW not seek formal recovery support Defence would nonetheless welcome the opportunity to engage with local government, particularly the City of Lithgow, to identify community groups and organisations that might benefit from such support, should NSW be agreeable to this," Head of the EMA Mark Crosweller wrote.

Mr Crossweller said 50 troops could work for five days in the region around Lithgow.

Up to 100 soldiers with engineering capabilities could be sent to the entire Blue Mountains region and other fire affected communities, and up to 120 general labourers and communications and logistic specialists sent from the Army Reserve.

The offer, which included reference to past defence support in the wake of disasters which has included construction of temporary housing and psychological support teams, included "capabilities ... above those usually made available."

Help from the army would come at no cost to the NSW Government and the Federal Government is expected to make the offer of assistance public today.

It is rare for the ADF to offer support of its own volition and usually waits for a formal request from government.

The NSW Government is yet to formally respond to the offer.

"It is unconventional," a senior Federal Government source said.

Late last week, Acting Chief of Defence Air Marshall Mark Binskin apologised for the bungled explosives training which sparked the blaze.

Defence has not offered compensation to those whose property was destroyed and is continuing to investigate the circumstances of the fire.

Explosives around where the live ordnance training was taking place made a small fire sparked during training unsafe to attempt to contain.

The fire started on a day of mild conditions and there were no fire bans.

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